1. Field of the Invention:
The present invention relates to a polishing medium or agent used for polishing silicon wafers and a polishing method using the same.
2. Description of the Related Art:
The polishing process is achieved in order to improve flatness and surface roughness of silicon wafers (hereinafter may be referred to, for brevity, as "wafer"). Insofar as the flatness is concerned, rigid polishing pads are preferable because the use of soft polishing pads results in deterioration of the flatness. However, the use of such rigid polishing pads encounter a problem that the surface roughness of polished wafers is very low. To improve the surface roughness, the wafers once polished by the rigid polishing pad should be polished again by using a soft polishing pad. Thus, the conventional polishing process should be a two-stage polishing process composed of a stock-removal rough polishing step using a rigid polishing pad, and a final polishing step using a soft polishing pad.